POSEIDON, quick tour

Ernesto

21st September, 2018

Research Questions

  • To NGOs:
    • Flight simulator
  • To academics:
    • Heuristics zoo
  • To other ABM practitioners:
    • Contribute to general problems

Agent Based Models

  • Define:
    • Behaviour of the individual
    • How they interact
  • Generate
    • Emergent patterns

Agent-Based Models and their use

  • Useful when
    • Feedback agent-environment-regulations
    • Heterogeneity (spatial, economic, etc..)
    • Individual data is available

Poseidon

What do you need for POSEIDON?

  • Coded in Java
  • Skill
    • Basic GUI
    • Input modifications
    • Algorithm modifications
  • Data needs
    • Conceptual model
    • Flexibility tradeoff
      • Confidence intervals vs data available

Pre-requisites - example

Decision Making is difficult

  • The profit maximizing boat; decides:
    • Where to fish
    • Optimal path
    • Number of trips per season
  • State space is immense:
    • Belief state of biomass available per fishing spot, per species, per time step
    • Location and action of all competitors
  • Bellman equation unsolvable

Pragmatism

  • Logbook data
  • Surveys
    • “I have only 5 spots and cycle through them”
    • “If in a bind, track highliner on radar and copy them”
    • “Explore a fixed proportion of tows”
    • “Draw peaks and valleys on maps”

Zoo approach

  • Collect decision algorithms
    • From interviews
    • From CS-literature
  • Implement them in the same agent-based model
    • Test strengths/weaknesses in theory
    • Compare to real data
  • Use it for policy suggestions and sensitivity analysis

Explore-Exploit-Imitate

Two Agents sample run

Many Agents

Cui prodest?

  • Model free
  • Adaptive

Fuel Prices

Fish the Line (part 1)

Fish the Line (part 2)

Fishing the Australian line

A flexible simulator

  • Flexible in terms of:
    • Fisher Behaviour
    • Biology
    • Management Measures (MPAs vs Quotas vs…)

Will fishers switch target in response to abundance changes?

POSEIDON adapts to other biological models

Optimization

USA West Coast - DTS fishery

  • Dover sole - thornyhead - sablefish complex
    • 110 boats, 3 states
    • Trawl
    • Multi-species
    • ITQ system (bycatch constrained)
  • Data rich:
    • Age structured stock assessment
    • Logbook data
    • Habitat data

Calibration strategy

Biology

Model run

Calibration

Validation

Resources

Partners